The pharmacologically active lignans sesamin and sesamolin are minor components of sesame oil and ingredients in OTC dietary supplement capsules. We report an introductory undergraduate organic laboratory experiment combining natural product isolation and spectral analysis in which students isolate a mixture of sesamin and sesamolin by either (1)…

This is an easy and inexpensive laboratory experiment in which undergraduate students at the Bachelor's degree level in Chemistry can measure formation constants of complexes [Ni(en)[subscript n](OH[subscript 2])[subscript 6-2n]][superscript 2]+ (n = 1, 2 or 3; en = ethylenediamine) through an acid-base titration. The background information…

Over the past decade the Accreditation Board for Engineering and Technology, Inc. (ABET) has changed the general chemistry requirements to include a single introductory course for most engineering majors. There is a focus on outcomes that equip students with the ability to pass the Fundamentals of Engineering (FE) Exam and to work in…

The binding constant and stoichiometry ratio for the formation of iron(II)-(1,10-phenanthroline) or iron(II)-o-phenanthroline complexes has been determined by a combination of a low-cost analytical method using a smartphone and a molecular modeling method as a laboratory experiment designed for analytical and physical chemistry courses. Intensity…

A simple and economical experimental setup is described that enables multiple individuals or groups within a laboratory class to measure the thermal melting of double stranded DNA simultaneously. The setup utilizes a basic spectrophotometer capable of measuring absorbance at 260 nm, UV plastic cuvettes, and a stirring hot plate. Students measure…

This paper presents the design and practical application of a laboratory inquiry at high school chemistry level for systematic chemistry learning, as exemplified by a thermochemical approach to the reaction stoichiometry of neutralization using Job's method of continuous variation. In the laboratory inquiry, students are requested to propose the…

A series of pedagogical problem set exercises are posed that illustrate the principles behind material efficiency green metrics and their application in developing a deeper understanding of reaction and synthesis plan analysis and strategies to optimize them. Rigorous, yet simple, mathematical proofs are given for some of the fundamental concepts,…

Stoichiometry has always been a puzzling subject. This may be partially due to the way it is introduced to students, with stoichiometric coefficients usually provided in the reaction. If the stoichiometric coefficients are not given, students find it very difficult to solve problems. This article describes a simple 4-h laboratory experiment for…

In this laboratory experiment, lower- and upper-division students dissolved bismuth subsalicylate tablets in acid and precipitated the resultant Bi[superscript 3+] in solution with sodium phosphate for a gravimetric determination of bismuth subsalicylate in the tablets. With a labeled concentration of 262 mg/tablet, the combined data from three…

A process for analyzing log files collected from open-ended learning environments is developed and tested on a virtual lab problem involving reaction stoichiometry. The process utilizes a set of visualization tools that, by grouping student actions in a hierarchical manner, helps experts make sense of the linear list of student actions recorded in…

A simple 3-h physical chemistry undergraduate experiment for the quantitative analysis of acetic acid in household vinegar is presented. The laboratory experiment combines titration concept with electrolysis and an application of the gas laws. A vinegar sample was placed in the cathode compartment of the electrolysis cell. Electrolysis of water…

A guided-inquiry lab, suitable for first-year general chemistry or high school advanced placement chemistry, is presented that uses only inexpensive, store-bought materials. The reaction of sodium bicarbonate (baking soda) with aqueous acetic acid (vinegar), under the constraint of the challenge to completely fill a sealable plastic bag with the…

The gasometric analysis of nitrogen produced in a reaction between sodium nitrite, NaNO[superscript 2], and sulfamic acid, H(NH[superscript 2])SO[superscript 3], provides an alternative to more common general chemistry experiments used to study the ideal gas law, such as the experiment in which magnesium is reacted with hydrochloric acid. This…

This project involved developing a method to remediate large quantities of aqueous waste from a general chemistry laboratory experiment. Aqueous Ni(II) waste from a general chemistry laboratory experiment was converted into solid nickel hydroxide hydrate with a substantial decrease in waste volume. The remediation method was developed for a…

This research study is an investigation of student-laboratory (i.e., lab) learning based on students' perceptions of experiences using questionnaire data and evidence of their science-laboratory performance based on paper-and-pencil assessments using Maryland-mandated criteria, Montgomery County Public Schools (MCPS) criteria, and published…